EDTA is a polyamino carboxylic acid (PACA) organic chelating agent used in many enzyme buffers and, at higher concentrations, as an enzyme inactivator. It is not only used in metal chelation, ion exchange and antioxidation procedures, but also in spectrophotometric titration and other chemical procedures. Its prominence as a chelating agent arises from its ability to sequester di- and tri-cationic metal ions such as Ca2+ and Fe3+. After being bound by EDTA, metal ions remain in solution while exhibiting diminished capacity as they are extensively enveloped and, as a consequence, their catalytic properties are often suppressed.
